Light-emitting device and electronic device

ABSTRACT

An object is to provide a light-emitting device having a structure in which an external connection portion can easily be connected and a method for manufacturing the light-emitting device. A light-emitting device includes a lower support  110 , a base insulating film  112  over the lower support  110  which has a through-hole  130 , a light-emitting element  127  over the base insulating film  112 , and an upper support  122  over the light-emitting element  127 . An electrode  131  is provided in the through-hole  130 , and the external connection terminal  132  electrically connected to the electrode  131  is provided below the base insulating film  112 . The external connection terminal  132  is electrically connected to the external connection portion  133  and functions as a terminal that inputs a signal or a power supply into the light-emitting device. This light-emitting device has a structure in which an external connection portion can easily be connected.

TECHNICAL FIELD

The present invention relates to a light-emitting device. Further, thepresent invention relates to an electronic device on which thelight-emitting device is mounted.

BACKGROUND ART

In recent years, there has been significant technological progress inthe field of displays. In particular, the needs of the market havestimulated tremendous progress in the technology directed to increasingresolution and thinning displays.

In the next phase of this field, focus is placed on commercialization offlexible displays having a curved display area, and a variety ofproposals have been made to increase the flexibility of displays (forexample, see Patent Document 1). In addition, light-emitting devicesusing a flexible substrate can be lightweight compared to those using asubstrate of usual thickness which is formed of glass or the like.

As methods for manufacturing a light-emitting device using a flexiblesubstrate, the following proposals have been made: a method in which alight-emitting element and other elements are directly provided over aflexible substrate; a method in which a light-emitting element is formedover a glass substrate of usual thickness and then the substrate issubjected to polishing treatment or the like, so that the substrate isthinned to have flexibility or the substrate is removed and thelight-emitting element is attached to a flexible substrate; a method inwhich a light-emitting element and other elements are formed over aglass substrate of usual thickness and then a layer having thelight-emitting element and the other elements is separated from thesubstrate and transferred to a flexible substrate; and the like.

Nevertheless, over a substrate having sufficient flexibility, alight-emitting element and other elements are not easy to form with highprecision. Therefore, over such a substrate, it is difficult to formlight-emitting elements for their respective colors or to provide acolor filter, much less to form a semiconductor element. Further, alight-emitting device using a thinned glass substrate can be said tolack sufficient flexibility. Even if a light-emitting device is formedby removal of a glass substrate, such a light-emitting device has aproblem of low productivity. In contrast, the method for manufacturing alight-emitting device in which a separation step and a transfer step areutilized is relatively simple and easy and facilitates fabrication of asemiconductor element or formation of light-emitting elements for theirrespective colors. This method can also ensure sufficient flexibility,which shows great promise.

Reference

-   [Patent Document]-   [Patent Document 1] Japanese Published Patent Application No.    2001-237064

DISCLOSURE OF INVENTION

Yet, it has been difficult to connect an external connection portiontypified by an FPC (flexible printed circuit) to a light-emitting deviceto which the above manufacturing method is applied.

Therefore, an object of one embodiment of the invention is to provide alight-emitting device having a structure that facilitates provision ofan external connection portion and a method for manufacturing thelight-emitting device.

The above object can be achieved with a light-emitting device providedwith an external connection terminal in a region where a through-holepenetrating an element formation layer is provided.

In other words, one embodiment of the present invention is alight-emitting device including a flexible lower support, a baseinsulating film being provided over the lower support and having athrough-hole, a light-emitting element provided over the base insulatingfilm, a flexible upper support provided over the light-emitting element,an electrode provided in the through-hole, an external connectionterminal provided below the base insulating film and electricallyconnected to the electrode, and an external connection portionelectrically connected to the external connection terminal.

Another embodiment of the present invention is a light-emitting deviceincluding a flexible lower support, a base insulating film beingprovided over the lower support and having a through-hole, alight-emitting element provided over the base insulating film, aflexible upper support provided over the light-emitting element, anexternal connection terminal provided in the through-hole, and anexternal connection portion provided below the base insulating film andelectrically connected to the external connection terminal.

Still another embodiment of the present invention is a light-emittingdevice having any of the above structures in which the lower support andthe external connection terminal are prevented from overlapping.

Yet another embodiment of the present invention is a light-emittingdevice having any of the above structures in which a protective memberis provided below the lower support and the external connection portion.

A still further embodiment of the present invention is a light-emittingdevice having any of the above structures in which the lower supportincludes a notch portion in a region where the external connectionterminal is formed.

Another embodiment of the present invention is a light-emitting devicein which an opening portion is provided in a region where the externalconnection terminal is formed.

Still another embodiment of the present invention is a light-emittingdevice in which the distance between a side (third side) of the lowersupport which is close to the external connection terminal and a side(fourth side) of the lower support which is opposite to the side closeto the external connection terminal is shorter than the distance betweena side (first side) of the light-emitting device which is provided withthe external connection terminal and a side (second side) of thelight-emitting device which is opposite to the side provided with theexternal connection terminal.

Yet another embodiment of the present invention is a light-emittingdevice having any of these structures in which the lower support coversat least part of the external connection portion.

In a light-emitting device having any of these structures, an externalconnection portion can easily be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B each illustrate a light-emitting device described inEmbodiment 1.

FIGS. 2A to 2E illustrate a manufacturing process of a light-emittingdevice described in Embodiment 1.

FIGS. 3A to 3C illustrate a manufacturing process of a light-emittingdevice described in Embodiment 1.

FIGS. 4A and 4B each illustrate a light-emitting device described inEmbodiment 1.

FIGS. 5A to 5C each illustrate a light-emitting device described inEmbodiment 1.

FIGS. 6A to 6C each illustrate a light-emitting device described inEmbodiment 1.

FIGS. 7A and 7B each illustrate a light-emitting device described inEmbodiment 1.

FIGS. 8A to 8E each illustrate an electronic device described inEmbodiment 2.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described withreference to the accompanying drawings. However, the present inventioncan be carried out in many different modes, and it is easily understoodby those skilled in the art that modes and details thereof can bemodified in various ways without departing from the spirit and the scopeof the present invention. Therefore, the present invention should not beinterpreted as being limited to the description of the embodiments.

(Embodiment 1)

A light-emitting device of this embodiment has an element formationlayer including a light-emitting element, a thin film transistor(hereinafter, referred to as a TFT), and the like between a flexibleupper support and a flexible lower support. The TFT is provided on thelower support side, and the light-emitting element is provided on theupper support side.

The above light-emitting device is formed in the following manner. Theelement formation layer including the TFT, the light-emitting element,and the like and the upper support are provided over a highlyheat-resistant substrate, such as a glass substrate, with a separationlayer interposed between the element formation layer and the substrate.After that, the element formation layer and the upper support areseparated at the separation layer, and this separation step forms aseparation surface, to which the lower support is then adhered. Notethat the light-emitting device may alternatively be formed by, forexample, a method in which, after the process up to the formation of theelement formation layer, which is provided with a separation substrate,the element formation layer is separated by using this substrate priorto the provision of the upper support, and then the upper support isattached to or replaced with the separation substrate. Unlike alight-emitting device formed over a glass substrate, a light-emittingdevice formed as above has a structure in which the lower support isattached to the element formation layer later, and thus the connectionterminal cannot be formed over the lower support beforehand. Therefore,the formation of a light-emitting device of this type requires complexand delicate work such as connecting an FPC before a separation step.

In the light-emitting device described in this embodiment, an externalconnection terminal is provided on the lower support side of the elementformation layer. The external connection terminal is electricallyconnected to an electrode of the TFT or an electrode of thelight-emitting element and supplies a signal generated in a power supplyor outside with the light-emitting device via an external connectionportion such as an FPC. Also via at least an electrode formed in athrough-hole provided in the base insulating film, the externalconnection terminal is electrically connected to the electrode of theTFT or the electrode of the light-emitting element.

The through-hole may be formed by any method as long as it penetratesthe base insulating film to expose a surface of the element formationlayer. The through-hole is connected to the electrodes of the TFT andthe light-emitting element through a contact hole, as appropriate.

Further, in the case where the external connection portion is connectedto the external connection terminal after the lower support is adhered,the lower support is not provided in a region where the externalconnection terminal is provided, i.e., the lower support and theexternal connection terminal are prevented from overlapping. In otherwords, the lower support in this case has a notch or an opening portionin the region where the external connection terminal may be provided.Alternatively, the external connection terminal may be exposed by usinga lower support the lateral length of which is shorter than that of theupper support by the lateral length of the external connection portion.In this case, in order to prevent damage to the external connectionportion, a protective member is preferably provided to cover theexternal connection portion and the lower support. When the lowersupport is adhered after the external connection portion is connected tothe external connection terminal, the lower support is provided to coverat least part of the external connection portion.

In the light-emitting device of this embodiment which has a structuredescribed above, the external connection portion can be connected afterthe separation step. Thus, the light-emitting device of this embodimentenables the external connection portion to be easily provided.

FIGS. 1A and 1B each illustrate the light-emitting device of thisembodiment.

FIG. 1A illustrates an example of the light-emitting device including adriver circuit region and a pixel region. Note that the driver circuitregion and the pixel region each have a TFT. Over a lower support 110, afirst adhesive layer 111 is provided. With the first adhesive layer 111,a base insulating film 112 and the lower support 110 are adhered to eachother. Over the base insulating film 112, a pixel TFT 114, a TFT 115 forthe driver circuit portion, and a first electrode 117 of alight-emitting element which is electrically connected to the pixel TFT114 are provided. Note that the number of each of these components inthe light-emitting device is more than one although not all of them areillustrated. A light-emitting element 127 includes the first electrode117 exposed from the partition wall 118, an EL layer 119 containing anorganic compound which is formed so as to cover at least the exposedfirst electrode 117, and a second electrode 120 which is provided tocover the EL layer 119. An upper support 122 is adhered on the secondelectrode 120 with a second adhesive layer 121. Further, in an externalconnection region, an external connection terminal 132 is provided belowthe base insulating film 112 and electrically connected to an electrode131 formed in a through-hole 130. Moreover, an external connectionportion 133 is connected to the external connection terminal 132. Notethat the lower support 110 is not provided in a region where theexternal connection terminal 132 is provided. Further, thelight-emitting device does not necessarily include the driver circuitregion. Further, the light-emitting device may have a CPU portion. Inaddition, here, an element formation layer 116 includes a layer from thebase insulating film 112 to the second electrode 120.

FIG. 1A illustrates the example in which the through-hole 130 penetratesfrom an interlayer insulating film 134 to the base insulating film 112.The electrode 131 provided in the through-hole 130 is connected to theelectrode of the TFT or the electrode of the light-emitting elementthrough a wiring such as a wiring 135 or a contact hole. Note that anelectrode 139 of FIG. 1A is a wiring electrode connected to a source ordrain region of the TFT.

FIG. 1B illustrates an example of a light-emitting device different fromthat of FIG. 1A. In FIG. 1B, the through-hole 130 penetrates a gateinsulating film 136 and the base insulating film. In such a case, theelectrode 131 provided in the through-hole 130 is connected to a wiringor an electrode provided on the interlayer insulating film 134, such asthe electrode 139, through an electrode 137 formed in a contact hole138.

Next, an example of a method for manufacturing the light-emitting deviceof this embodiment is described with reference to FIGS. 2A to 2E.

First, the base insulating film 112 is formed over a formation substrate200 having an insulating surface with a separation layer 201 interposedtherebetween. Over the base insulating film 112, a semiconductor layer250, a gate insulating film 251, a gate electrode 252, a protectiveinsulating film 253, and an interlayer insulating film 254 are furtherformed (see FIG. 2A).

The separation layer 201 is formed by a sputtering method, a plasma CVDmethod, a coating method, a printing method, or the like as a singlelayer or a stacked layer using an element such as tungsten (W),molybdenum (Mo), titanium (Ti), tantalum (Ta), niobium (Nb), nickel(Ni), cobalt (Co), zirconium (Zr), zinc (Zn), ruthenium (Ru), rhodium(Rh), palladium (Pd), osmium (Os), iridium (Ir), or silicon (Si): analloy material containing the element as its main component; or acompound material containing the element as its main component. Notethat in the case where the separation layer includes silicon, siliconmay be any one of an amorphous state, a microcrystalline state, and apolycrystalline state. Here, the term coating method includes aspin-coating method, a droplet discharge method, a dispensing method, anozzle-printing method, and a slot die coating method.

When the separation layer 201 has a single layer structure, it ispreferable to form a tungsten layer, a molybdenum layer, or a layercontaining a mixture of tungsten and molybdenum. Alternatively, a layercontaining an oxide or an oxynitride of tungsten, a layer containing anoxide or an oxynitride of molybdenum, or a layer containing an oxide oran oxynitride of a mixture of tungsten and molybdenum is formed. Notethat the mixture of tungsten and molybdenum corresponds to an alloy oftungsten and molybdenum, for example.

In the case where the separation layer 201 has a stack structure, it ispreferable that a first layer be formed using a tungsten layer, amolybdenum layer, or a layer containing a mixture of tungsten andmolybdenum and a second layer be formed using an oxide, a nitride, anoxynitride, or a nitride oxide of tungsten, molybdenum, or a mixture oftungsten and molybdenum.

In the case where the separation layer 201 has a stack structure of alayer containing tungsten and a layer containing an oxide of tungsten,the layer containing tungsten may be formed first and an insulatinglayer formed of an oxide may be formed over the layer containingtungsten so that the layer containing an oxide of tungsten can be formedat an interface between the tungsten layer and the insulating layer.Further, the surface of the layer containing tungsten may be subjectedto thermal oxidation treatment, oxygen plasma treatment, or treatmentusing a strong oxidizing solution such as ozone water to form the layercontaining an oxide of tungsten. Furthermore, plasma treatment or heattreatment may be performed in an atmosphere of an elementary substanceof oxygen, nitrogen, dinitrogen monoxide, dinitrogen monoxide, or amixed gas of any of these gases and another gas. Note that these methodscan also be applied to formation of a stack structure of a layerincluding tungsten and a layer including nitride, oxynitride or nitrideoxide of tungsten. Specifically, after the layer including tungsten isformed, the layer including silicon nitride, silicon oxynitride, orsilicon nitride oxide of tungsten can be obtained by nitridation,oxynitridation, or nitridation oxidation or alternatively, by formationof a silicon nitride layer, a silicon oxynitride layer, or a siliconnitride oxide layer over the layer including tungsten.

Next, the base insulating film 112 is formed. The base insulating film112 may have a single layer structure or a stack structure. When thebase insulating film 112 has a stack structure, it preferably includes afilm that is dense and has a high blocking property for inhibiting entryof a substance, such as moisture or metal, which promotes deteriorationof the light-emitting element or TFT and a film for stabilizingproperties of the TFT.

As the film having a high blocking property, there is an insulating filmcontaining nitrogen and silicon, such as a film containing siliconnitride, silicon oxynitride, or silicon nitride oxide. The film having ahigh blocking property is formed by, for instance, a plasma CVD methodunder conditions where the temperature is set to 250 to 400° C. and theothers are set as known.

The film for stabilizing properties of the TFT can be formed by using aninorganic insulating film of silicon oxide, silicon nitride, siliconoxynitride, silicon nitride oxide, or the like.

The semiconductor layer 250 serving as an active layer of the TFT can beformed using any of the following materials: an amorphous semiconductorformed by a vapor-phase growth method using a semiconductor source gastypified by silane or germane or a sputtering method; a polycrystallinesemiconductor formed by crystallizing the amorphous semiconductor withthe use of light energy or thermal energy; a microcrystalline (alsoreferred to as semi-amorphous or microcrystal) semiconductor; asemiconductor containing an organic material as its main component; andthe like. The semiconductor layer 250 can be formed by a sputteringmethod, an LPCVD method, a plasma CVD method, or the like.

The microcrystalline semiconductor belongs to an intermediate metastablestate between an amorphous semiconductor and a single crystalsemiconductor when Gibbs free energy is considered. In other words, themicrocrystalline semiconductor layer is a semiconductor layer having athird state which is stable in terms of free energy and has a shortrange order and lattice distortion. Columnar-like or needle-likecrystals grow in a normal direction with respect to a substrate surface.The Raman spectrum of microcrystalline silicon, which is a typicalexample of a microcrystalline semiconductor, is shifted to a wave numberlower than 520 cm⁻¹, which represents a peak of the Raman spectrum ofsingle crystal silicon. In other words, the peak of the Raman spectrumof the microcrystalline silicon exists between 520 cm⁻¹ which representssingle crystal silicon and 480 cm⁻¹ which represents amorphous silicon.The microcrystalline silicon contains hydrogen or halogen of at least 1at. % to terminate a dangling bond. Moreover, microcrystalline siliconis made to contain a rare gas element such as helium, argon, krypton, orneon to further enhance its lattice distortion, whereby stability isincreased and a favorable microcrystalline semiconductor film can beobtained.

This microcrystalline semiconductor film can be formed by ahigh-frequency plasma CVD method with a frequency of several tens of MHzto several hundreds of MHz or with a microwave plasma CVD method with afrequency of greater than or equal to 1 GHz. The microcrystallinesemiconductor film can be formed in such a manner that silicon hydride,typically, SiH₄, Si₂H₆, SiH₂Cl₂, SiHCl₃, SiCl₄, SiF₄, or the like isdiluted with hydrogen. With a dilution with one or plural kinds of raregas elements selected from helium, argon, krypton, and neon in additionto silicon hydride and hydrogen, the microcrystalline semiconductor filmcan be formed. In that case, the flow ratio of hydrogen to siliconhydride is set to 5:1 to 200:1, preferably, 50:1 to 150:1, morepreferably, 100:1.

As a typical example of an amorphous semiconductor, hydrogenatedamorphous silicon can be given, and as an example of a crystallinesemiconductor, polysilicon or the like can be given. Typical examples ofpolysilicon (polycrystalline silicon) include so-called high-temperaturepolysilicon that contains polysilicon which is formed at a processtemperature of greater than or equal to 800° C. as its main component,so-called low-temperature polysilicon that contains polysilicon which isformed at a process temperature of less than or equal to 600° C. as itsmain component, polysilicon obtained by crystallizing amorphous siliconby using an element that promotes crystallization or the like, and thelike. It is needless to say that as mentioned above, a microcrystallinesemiconductor or a semiconductor containing a crystal phase in a part ofa semiconductor layer can be used.

As a material of the semiconductor layer, as well as an element such assilicon (Si) or germanium (Ge), a compound semiconductor such as GaAs,InP, SiC, ZnSe, GaN, or SiGe can be used. Alternatively, an oxidesemiconductor such as zinc oxide (ZnO), tin oxide (SnO₂), magnesium zincoxide, gallium oxide, or indium oxide, an oxide semiconductor includingtwo or more of the above oxide semiconductors, or the like can be used.For example, an oxide semiconductor including zinc oxide, indium oxide,and gallium oxide can also be used. In the case of using the oxidesemiconductor for the semiconductor layer, the gate insulating film maybe formed using Y₂O₃, Al₂O₃, or TiO₂, a stacked layer thereof, or thelike, and the gate electrode layer, the source electrode layer, and thedrain electrode layer may be formed using ITO, Au, Ti, or the like. Inaddition, In, Ga, or the like can be added to ZnO.

In the case of using a crystalline semiconductor layer for thesemiconductor layer, the crystalline semiconductor layer may be formedby any of various methods (such as a laser crystallization method, athermal crystallization method, and a thermal crystallization methodusing an element promoting crystallization, such as nickel). Also, amicrocrystalline semiconductor can be crystallized by being irradiatedwith laser light to increase its crystallinity. When the element thatpromotes crystallization is not introduced, prior to irradiating anamorphous silicon film with laser light, the amorphous silicon film isheated at 500° C. for one hour under a nitrogen atmosphere to releasehydrogen contained in the amorphous silicon film so that theconcentration of hydrogen is reduced to 1×10²⁰ atoms/cm³ or lower. Thisis because the amorphous silicon film is destroyed when the amorphoussilicon film containing a high amount of hydrogen is irradiated withlaser light.

A method for introducing a metal element into an amorphous semiconductorlayer is not limited to a particular method as long as it is a methodcapable of providing the metal element on a surface or inside of theamorphous semiconductor layer. For example, a sputtering method, a CVDmethod, a plasma processing method (including a plasma CVD method), anadsorption method, or a method for applying a solution of metal salt,can be used. In the above mentioned methods, the method using a solutionis simple and has an advantage that the concentration of a metal elementcan easily be adjusted. In addition, at this time, in order to improvethe wettability of the surface of the amorphous semiconductor layer tospread an aqueous solution on the entire surface of the amorphoussemiconductor layer, an oxide film is preferably formed by UV lightirradiation in an oxygen atmosphere, a thermal oxidation method,treatment using ozone water containing hydroxy radical or a hydrogenperoxide solution, or the like.

In addition, in a crystallization step in which the amorphoussemiconductor layer is crystallized to form a crystalline semiconductorlayer, the crystallization may be performed by adding an element thatpromotes crystallization (also referred to as a catalyst element or ametal element) to the amorphous semiconductor layer and performing heattreatment (at 550 to 750° C. for 3 minutes to 24 hours). As the elementthat promotes (accelerates) the crystallization, one or more of iron(Fe), nickel (Ni), cobalt (Co), ruthenium (Ru), rhodium (Rh), palladium(Pd), osmium (Os), iridium (Ir), platinum (Pt), copper (Cu), and gold(Au) can be used.

In order to remove or reduce the element which promotes crystallizationfrom the crystalline semiconductor layer, a semiconductor layercontaining an impurity element is formed in contact with the crystallinesemiconductor layer and is made to function as a gettering sink. As theimpurity element, an impurity element imparting n-type conductivity, animpurity element imparting p-type conductivity, a rare gas element, orthe like can be used. For example, one or more of phosphorus (P),nitrogen (N), arsenic (As), antimony (Sb), bismuth (Bi), boron (B),helium (He), neon (Ne), argon (Ar), krypton (Kr), and xenon (Xe) can beused. The semiconductor layer containing a rare gas element is formedover the crystalline semiconductor layer containing an element whichpromotes crystallization, and heat treatment (at 550 to 750° C. for 3minutes to 24 hours) is performed. The element that promotescrystallization in the crystalline semiconductor layer moves into thesemiconductor layer containing a rare gas element, and the element thatpromotes crystallization in the crystalline semiconductor layer isremoved or reduced. Then, the semiconductor layer containing a rare gaselement, which serves as a gettering sink, is removed.

The amorphous semiconductor layer may be crystallized by usingcombination of heat treatment and laser light irradiation. The heattreatment or the laser light irradiation may be carried out severaltimes, separately.

Alternatively, the crystalline semiconductor layer may be directlyformed over the substrate by a plasma method. Alternatively, thecrystalline semiconductor layer may be selectively formed over thesubstrate by a plasma method.

As the semiconductor film containing an organic material as its maincomponent, a semiconductor film containing, as its main component, asubstance which contains a certain amount of carbon or an allotrope ofcarbon (excluding diamond), which is combined with another element, canbe used. Specifically, pentacene, tetracene, a thiophene oligomerderivative, a phenylene derivative, a phthalocyanine compound, apolyacetylene derivative, a polythiophene derivative, a cyanine dye, andthe like can be given.

The gate insulating film 251 and the gate electrode 252 may be formed tohave a known structure by a known method. For example, the gateinsulating film 251 may be formed to have a known structure such as asingle layer structure of silicon oxide or a stack structure includingsilicon oxide and silicon nitride, and the gate electrode 252 may beformed using any of Ag, Au, Cu, Ni, Pt, Pd, Ir, Rh, W, Al, Ta, Mo, Cd,Zn, Fe, Ti, Si, Ge, Zr, and Ba; or an alloy material or a compoundmaterial containing any of the elements as its main component by a CVDmethod, a sputtering method, a droplet discharge method, or the like. Inaddition, a semiconductor film typified by a polycrystalline siliconfilm doped with an impurity element such as phosphorus, or an AgPdCualloy may be used. Further, either a single layer structure or a stackstructure may be employed.

Note that the top gate transistor illustrated as an example maynaturally be replaced with a bottom gate transistor or a transistorhaving any other known structure.

Next, the protective insulating film 253 including an inorganicinsulating material and then the interlayer insulating film 254including an organic or inorganic insulating material are formed. As theinorganic insulating material, silicon oxide, silicon nitride, siliconoxynitride, silicon nitride oxide, or the like can be used. As theorganic insulating material, acrylic, polyimide, polyamide,polyimideamide, benzocyclobutene, or the like can be used.

After the interlayer insulating film 254 is formed, by patterning andetching, contact holes reaching the semiconductor layer 250 of the TFTare formed in the interlayer insulating film 254, the protectiveinsulating film 253, and the gate insulating film 251, and thethrough-hole is formed in the interlayer insulating film 254, theprotective insulating film 253, the gate insulating film 251, and thebase insulating film 112. The through-hole is formed by continuing theetching even after the contact holes reach the semiconductor layer 250.As the etching at this time, a method and conditions are selected suchthat the selection ratio of the interlayer insulating film 254, theprotective insulating film 253, the gate insulating film 251, and thebase insulating film 112 to the semiconductor layer 250 is sufficientlyhigh.

After that, the electrode 131 is formed in the through-hole while thewiring electrode such as the electrode 139 is formed in the contactholes. The electrode 131 and the electrode 139 may be formed in the samestep or using different materials in different steps.

Alternatively, the through-hole and the contact holes may be formed indifferent steps. In this case, the formation of the through-hole andoxidation treatment by O2 ashing or the like on the exposed surface ofthe separation layer 201 can precede the formation of the electrode 131.Accordingly, adhesion between the electrode 131 and the separation layer201 can be reduced to facilitate the separation in a later separationstep (see FIG. 2B).

Then, the first electrode 117 is formed using a transparent conductivefilm. When the first electrode 117 is an anode, indium oxide (In₂O₃), analloy of indium oxide and tin oxide (In₂O₃—SnO₂: ITO), or the like canbe used as a material of the transparent conductive film, and the firstelectrode 117 can be formed by a sputtering method, a vacuum evaporationmethod, or the like. Alternatively, an alloy of indium oxide and zincoxide (In₂O₃—ZnO) may be used. In addition, zinc oxide (ZnO) is also anappropriate material, and moreover, zinc oxide to which gallium (Ga) isadded to increase conductivity and a light-transmitting property withrespect to visible light, or the like can be used. When the firstelectrode 117 is a cathode, an extremely thin film of a material with alow work function such as aluminum can be used. Alternatively, a stackstructure which has a thin layer of such a substance and theabove-mentioned transparent conductive film can be employed.

Then, the insulating film 254 is formed using an organic or inorganicinsulating material so as to cover the interlayer insulating film andthe first electrode 117. The insulating film is processed such that thesurface of the first electrode 117 is exposed and the insulating filmcovers an end portion of the first electrode 117, whereby the partitionwall 118 is formed.

Then, the EL layer 119 is formed. There is no particular limitation on astack structure of the EL layer 119 as long as it is formed by combininglayers including a substance having a high electron-transport property,a substance having a high hole-transport property, a substance having ahigh electron-injection property, a substance having a highhole-injection property, a bipolar substance (a substance having a highelectron-transport property and a high hole-transport property), alight-emitting substance, and/or the like, as appropriate. For example,an appropriate combination of any of a hole-injection layer, ahole-transport layer, a light-emitting layer, an electron-transportlayer, an electron-injection layer, and the like can be formed. In thisembodiment, a structure is explained in which the EL layer 119 includesa hole-injection layer, a hole-transport layer, a light-emitting layer,and an electron-transport layer. Specific materials to form each of thelayers are given below.

The hole-injection layer is a layer that is provided in contact with ananode and contains a substance having a high hole-injection property.Specifically, molybdenum oxide, vanadium oxide, ruthenium oxide,tungsten oxide, manganese oxide, or the like can be used. Alternatively,the hole-injection layer can also be formed using any of the followingmaterials: phthalocyanine compounds such as phthalocyanine (abbreviatedto H₂PC) and copper phthalocyanine (abbreviated to CuPc); aromatic aminecompounds such as4,4′-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviatedto DPAB) and4,4′-bis(N-{4-[N′-methylphenyl)-N-phenylamino]phenyl}-N′-phenylamino)biphenyl(abbreviated to DNTPD); high-molecular compounds such aspolyethylenedioxythiophene/polystyrenesulfonic acid (abbreviated toPEDOT/PSS); and the like.

Alternatively, as the hole-injection layer, a composite materialcontaining a substance having a high hole-transport property and anacceptor substance can be used. Note that, by using the compositematerial containing the substance having a high hole-transport propertyand the acceptor substance, a material used to form an electrode can beselected regardless of its work function. In other words, besides amaterial with a high work function, a material with a low work functioncan also be used as the first electrode 117. As the acceptor substance,7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviated toF₄-TCNQ), chloranil, and the like can be given. In addition, as theacceptor substance, a transition metal oxide is given. In addition,oxides of metals that belong to Group 4 to Group 8 of the periodic tableare given. Specifically, vanadium oxide, niobium oxide, tantalum oxide,chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, andrhenium oxide are preferable because of their high electron-acceptingproperties. Among these metal oxides, molybdenum oxide is preferablesince it can be easily treated due to its stability in air and lowhygroscopic property.

As the substance having a high hole-transport property used for thecomposite material, any of various compounds such as aromatic aminecompounds, carbazole derivatives, aromatic hydrocarbons, orhigh-molecular compounds (such as oligomers, dendrimers, or polymers)can be used. Note that the organic compound used for the compositematerial is preferably an organic compound having a high hole-transportproperty. Specifically, a substance having a hole mobility of greaterthan or equal to 10⁻⁶ cm²/Vs is preferably used. However, othersubstances than these substances may also be used as long as thehole-transport property thereof is higher than the electron-transportproperty thereof. The organic compound that can be used for thecomposite material is specifically shown below.

Examples of the aromatic amine compounds includeN,N′-di(p-tolyl)-N,N′-diphenyl-p-phenylenediamine (abbreviated toDTDPPA), 4,4′-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl(abbreviated to DPAB),4,4′-bis(N-{4-[N′(3-methylphenyl)-N-phenylamino]phenyl}-phenylamino)biphenyl(abbreviated to DNTPD),1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviatedto DPA3B), and the like.

Examples of the carbazole derivatives which can be used for thecomposite material include3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole(abbreviated to PCzPCA1),3,6-bis[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole(abbreviated to PCzPCA2),3-[N-(1-naphtyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole(abbreviated to PCzPCN1), and the like.

In addition, examples of the carbazole derivatives which can be used forthe composite material include 4,4′-di(N-carbazolyl)biphenyl(abbreviated to CSP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene(abbreviated to TCPB), 9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole(abbreviated to CzPA),1,4-bis[4-(N-carbazolyl)phenyl]-2,3,5,6-tetraphenylbenzene, and thelike.

Examples of the aromatic hydrocarbons which can be used for thecomposite material include 2-tert-butyl-9,10-di(2-naphthyl)anthracene(abbreviated to t-BuDNA), 2-tert-butyl-9,10-di(1-naphthyl)anthracene,9,10-bis(3,5-diphenylphenyl)anthracene (abbreviated to DPPA),2-tert-butyl-9,10-bis(4-phenylphenyl)anthracene (abbreviated tot-BuDBA), 9,10-di(2-naphthyl)anthracene (abbreviated to DNA),9,10-diphenylanthracene (abbreviated to DPAnth), 2-tert-butylanthracene(abbreviated to t-BuAnth), 9,10-bis(4-methyl-1-naphthyl)anthracene(abbreviated to DMNA),2-tert-butyl-9,10-bis[2-(1-naphthyl)phenyl]anthracene,9,10-bis[2-(1-naphthyl)phenyl]anthracene,2,3,6,7-tetramethyl-9,10-di(1-naphthyl)anthracene,2,3,6,7-tetramethyl-9,10-di(2-naphthyl)anthracene, 9,9′-bianthryl,10,10′-diphenyl-9,9′-bianthryl,10,10′-bis(2-phenylphenyl)-9,9′-bianthryl,10,10′-bis[(2,3,4,5,6-pentaphenyl)phenyl]-9,9′-bianthryl, anthracene,tetracene, rubrene, perylene, 2,5,8,11-tetra(tert-butyl)perylene, andthe like. As well as these compounds, pentacene, coronene, or the likecan be used. Note that when an aromatic hydrocarbon having a holemobility of greater than or equal to 1×10⁻⁶ cm²/Vs is selected and anevaporation method is used to form a film of the aromatic hydrocarbon,the number of the carbon atoms that forms a condensed ring is preferably14 to 42 in terms of evaporativity at the time of evaporation or filmquality after the film formation.

Note that the aromatic hydrocarbon that can be used for the compositematerial may have a vinyl skeleton. As an aromatic hydrocarbon having avinyl group, for example, 4,4′-bis(2,2-diphenylvinyl)biphenyl(abbreviated to DPVBi), 9,10-bis[4-(2,2-diphenylvinyl)phenyl]anthracene(abbreviated to DPVPA), and the like are given.

High-molecular compounds such as poly(N-vinylcarbazole) (abbreviated toPVK), poly(4-vinyltriphenylamine) (abbreviated to PVTPA),poly[N-(4-{N′[4-(4-diphenylamino)phenyl]phenyl-N′-phenylamino}phenyl)methacrylamide](abbreviatedto PTPDMA), poly[N,N′-bis(4-butylphenyl)-N,N′-bis(phenyl)benzidine](abbreviated to Poly-TPD), and the like can also be used.

The hole-transport layer is a layer that contains a substance having ahigh hole-transport property. Examples of the substance having a highhole-transport property include aromatic amine compounds such as4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviated to NPB),N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1′-biphenyl]-4,4′-diamine(abbreviated to TPD), 4,4′,4″-tris(N,N-diphenylamino)triphenylamine(abbreviated to TDATA),4,4′,4″-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine(abbreviated to MTDATA),4,4′-bis[N-(spiro-9,9′-bifluoren-2-yl)-N-phenylamino]biphenyl(abbreviated to BSPB), and the like. The substances described here aremainly substances having a hole mobility of greater than or equal to10′⁶ cm²/Vs. However, a substance other than the above-describedsubstances may also be used as long as the hole-transport propertythereof is higher than the electron-transport property thereof. Notethat the layer containing the substance having a high hole-transportproperty is not limited to a single layer, and two or more layerscontaining the aforementioned substances may be stacked.

Further, a high-molecular compound such as poly(N-vinylcarbazole)(abbreviated to PVK) or poly(4-vinyltriphenylamine) (abbreviated toPVTPA) can also be used for the hole-transport layer.

The light-emitting layer is a layer containing a light-emittingsubstance. The light-emitting layer may be a so-called singlelight-emitting layer containing a light-emitting substance as its maincomponent or a so-called host-guest type light-emitting layer in which alight-emitting substance is dispersed in a host material.

There is no particular limitation on the light-emitting substance thatis used, and known fluorescent materials or phosphorescent materials canbe used. As fluorescent materials, for example, in addition toN,N′-bis[4-(9H-carbazol-9-yl)phenyl]-N,N′-diphenylstilbene-4,4′-diamine(abbreviated to YGA2S),4-(9H-carbazol-9-yl)-4′-(10-phenyl-9-anthryl)triphenylamine (abbreviatedto YGAPA), and the like, there are fluorescent materials with anemission wavelength of greater than or equal to 450 nm, such as4-(9H-carbazol-9-yl)-4′-(9,10-diphenyl-2-anthryl)triphenylamine(abbreviated to 2YGAPPA),N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine(abbreviated to PCAPA), perylene, 2,5,8,11-tetra-tert-butylperylene(abbreviated to TBP),4-(10-phenyl-9-anthryl)-4′-(9-phenyl-9H-carbazol-3-yl)triphenylamine(abbreviated to PCBAPA),N,N″-(2-tert-butylanthracene-9,10-diyldi-4,1-phenylene)bis[N,N′,N′-triphenyl-1,4-phenylenediamine](abbreviatedto DPABPA),N,9-diphenyl-N-[4-(9,10-diphenyl-2-anthryl)phenyl]-9H-carbazol-3-amine(abbreviated to 2PCAPPA),N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N′,N′-triphenyl-1,4-phenylenediamine(abbreviated to 2DPAPPA),N,N,N′,N′,N″,N″,N′″,N′″-octaphenyldibenzo[g,p]chrysene-2,7,10,15-tetraamine(abbreviated to DBC1), coumarin 30,N-(9,10-diphenyl-2-anthryl)-N,9-diphenyl-9H-carbazol-3-amine(abbreviated to 2 PCAPA),N-[9,10-bis(1,1′-biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazol-3-amine(abbreviated to 2PCABPhA),N-(9,10-diphenyl-2-anthryl)-N,N′,N′-triphenyl-1,4-phenylenediamine(abbreviated to 2DPAPA),N-[9,10-bis(1,1′-biphenyl-2-yl)-2-anthryl]-N,N′,N′-triphenyl-1,4-phenylenediamine(abbreviated to 2DPABPhA),9,10-bis(1,1′-biphenyl-2-yl)-N-[4-(9H-carbazol-9-yl)phenyl]-N-phenylanthracen-2-amine(abbreviated to 2YGABPhA), N,N,9-triphenylanthracen-9-amine (abbreviatedto DPhAPhA), coumarin 545T, N,N′-diphenylquinacridone (abbreviated toDPQd), rubrene, 5,12-bis(1,1′-biphenyl-4-yl)-6,11-diphenyltetracene(abbreviated to BPT),2-(2-{2-[4-(dimethylamino)phenyl]ethenyl}-6-methyl-4H-pyran-4-ylidene)propanedinitrile(abbreviated to DCM1),2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile(abbreviated to DCM2),N,N,N′,N′-tetrakis(4-methylphenyl)tetracene-5,11-diamine (abbreviated top-mPhTD),7,14-diphenyl-N,N,N′,N′-tetrakis(4-methylphenyl)acenaphtho[1,2-α]fluoranthene-3,10-diamine(abbreviated to p-mPhAFD),2-{2-isopropyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviated to DCJTI),2-{2-tert-butyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile(abbreviated to DCJTB),2-(2,6-bis{2-[4-(dimethylamino)phenyl]ethenyl}-4H-pyran-4-ylidene)propanedinitrile(abbreviated to BisDCM), and2-{2,6-bis[2-(8-methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile(abbreviated to BisDCJTM). As phosphorescent materials, for example, inaddition tobis[2-(4′,6′-difluorophenyl)pyridinato-N,C^(2′)]iridium(III)tetrakis(1-pyrazolyl)borate(abbreviated to FIr6) and the like, there are phosphorescent materialswith an emission wavelength in the range of 470 nm to 500 nm, such asbis[2-(4′,6′-difluorophenyl)pyridinato-N,C^(2′)]iridium(III)picolinate(abbreviated to FIrpic),bis[2-(3′,5′-bistrifluoromethylphenyl)pyridinato-N,C²′]iridium(III)picolinate(abbreviated to Ir(CF₃ppy)₂(pic)), andbis[2-(4′,6′-difluorophenyl)pyridinato-N,C^(2′)]iridium(III)acetylacetonate(abbreviated to FIracac); phosphorescent materials with an emissionwavelength of greater than or equal to 500 nm (materials which emitgreen light), such as tris(2-phenylpyridinato)iridium(III) (abbreviatedto Ir(ppy)₃), bis(2-phenylpyridinato)iridium(III)acetylacetonate(abbreviated to Ir(ppy)₂(acac)),tris(acetylacetonato)(monophenanthroline)terbium(III) (abbreviated toTb(acac)₃(Phen)), bis(benzo[h]quinolinato)iridium(III)acetylacetonate(abbreviated to Ir(bzq)₂(acac)),bis(2,4-diphenyl-1,3-oxazolato-N,C^(2′))iridium(III)acetylacetonate(abbreviated to Ir(dpo)₂(acac)),bis[2-(4′-perfluorophenylphenyl)pyridinato]iridium(III)acetylacetonate(abbreviated to Ir(p-PF-ph)₂(acac)),bis(2-phenylbenzothiazolato-N,C^(2′))iridium(III)acetylacetonate(abbreviated to Ir(bt)₂(acac)),bis[2-(2′-benzo[4,5-α]thienyl)pyridinato-N,C³′]iridium(III)acetylacetonate(abbreviated to Ir(btp)₂(acac)),bis(1-phenylisoquinolinato-N,C^(2′))iridium(III)acetylacetonate(abbreviated to Ir(piq)₂(acac)),(acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III)(abbreviated to Ir(Fdpq)₂(acac)),(acetylacetonato)bis(2,3,5-triphenylpyrazinato)iridium(III) (abbreviatedto Ir(tppr)₂(acac)),2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrinatoplatinum(II)(abbreviated to PtOEP),tris(1,3-diphenyl-1,3-propanedionato)(monophenanthroline)europium(III)(abbreviated to Eu(DBM)₃(Phen)), andtris[1-(2-thenoyl)-3,3,3-trifluoroacetonato](monophenanthroline)europium(III)(abbreviated to Eu(TTA)₃(Phen)); and the like. The light-emittingsubstances can be selected from the above-mentioned materials or otherknown materials in consideration of the emission color of each of thelight-emitting elements.

When the host material is used, there are, for example, metal complexessuch as tris(8-quinolinolato)aluminum(III) (abbreviated to Alq),tris(4-methyl-8-quinolinolato)aluminum(III) (abbreviated to Almq₃),bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviated to BeBq₂),bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III)(abbreviated to BAlq), bis(8-quinolinolato)zinc(II) (abbreviated toZnq), bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviated to ZnPBO),and bis[2-(2-benzothiazoly)phenolato]zinc(II) (abbreviated to ZnBTZ);heterocyclic compounds such as2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviated toPBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene(abbreviated to OXD-7),3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole(abbreviated to TAZ),2,2′,2″-(1,3,5-benzenetriyl)-tris(1-phenyl-1H-benzimidazole)(abbreviated to TPBI), bathophenanthroline (abbreviated to BPhen),bathocuproine (abbreviated to BCP), and9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviated toCO11); and aromatic amine compounds such as NPB (or α-NPD), TPD, andBSPB. In addition, condensed polycyclic aromatic compounds such asanthracene derivatives, phenanthrene derivatives, pyrene derivatives,chrysene derivatives, and dibenzo[g,p]chrysene derivatives are given.Specific examples of the condensed polycyclic aromatic compounds include9,10-diphenylanthracene (abbreviated to DPAnth),N,N-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine(abbreviated to CzA1PA), 4-(10-phenyl-9-anthryl)triphenylamine(abbreviated to DPhPA),4-(9H-carbazol-9-yl)-4′-(10-phenyl-9-anthryl)triphenylamine (abbreviatedto YGAPA),N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine(abbreviated to PCAPA),N,9-diphenyl-N-{4-[4-(10-phenyl-9-anthryl)phenyl}phenyl]-9H-carbazol-3-amine(abbreviated to PCAPBA),N-9-diphenyl-N-(9,10-diphenyl-2-anthryl)-9H-carbazol-3-amine(abbreviated to 2PCAPA), 6,12-dimethoxy-5,11-diphenylchrysene,N,N,N′,N′,N″,N″,N′″,N′″-octaphenyldibenzo[g,p]chrysene-2,7,10,15-tetramine(abbreviated to DBC1), 9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole(abbreviated to CzPA),3,6-diphenyl-9-[4-(10-phenyl-9-antryl)phenyl]-9H-carbazole (abbreviatedto DPCzPA), 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviated toDPPA), 9,10-di(2-naphthyl)anthracene (abbreviated to DNA),2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviated to t-BuDNA),9,9′-bianthryl (abbreviated to BANT),9,9′-(stilbene-3,3′-diyl)diphenanthrene (abbreviated to DPNS),9,9′-(stilbene-4,4′-diyl)diphenanthrene (abbreviated to DPNS2),3,3′,3″-(benzene-1,3,5-triyl)tripyrene (abbreviated to TPB3), and thelike. From these substances or other known substances, the host materialmay be selected so that the host material has a larger energy gap (ortriplet excitation energy if the light-emitting substance emitsphosphorescence) than the light-emitting substance dispersed in thelight-emitting layer and has a carrier-transport property required foreach of the light-emitting layers.

The electron-transport layer is a layer that contains a substance havinga high electron-transport property. For example, a layer containing ametal complex having a quinoline skeleton or a benzoquinoline skeleton,such as tris(8-quinolinolato)aluminum (abbreviated to Alq),tris(4-methyl-8-quinolinolato)aluminum (abbreviated to Almq₃),bis(10-hydroxybenzo[h]-quinolinato)beryllium (abbreviated to BeBq₂), orbis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum (abbreviated toBAlq) can be used. Alternatively, a metal complex having anoxazole-based or thiazole-based ligand, such asbis[2-(2-hydroxyphenyl)benzoxazolato]zinc (abbreviated to Zn(BOX)₂) orbis[2-(2-hydroxyphenyl)benzothiazolato]zinc (abbreviated to Zn(BTZ)₂)can be used. Besides the metal complexes,2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviated toPBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene(abbreviated to OXD-7),3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole(abbreviated to TAZ), bathophenanthroline (abbreviated to BPhen),bathocuproine (abbreviated to BCP), or the like can also be used. Thesubstances described here are mainly those having an electron mobilityof greater than or equal to 10⁻⁶ cm²/Vs. Note that a substance otherthan the above substances may also be used as the electron-transportlayer as long as the electron-transport property thereof is higher thanthe hole-transport property thereof.

Further, the electron-transport layer may be formed as not only a singlelayer but also as a stacked layer in which two or more layers formedusing the above mentioned substances are stacked.

Further, a layer for controlling transport of electrons may be providedbetween the electron-transport layer and the light-emitting layer. Thelayer for controlling transport of electrons is a layer in which a smallamount of a substance having a high electron-trapping property is addedto a layer containing the above-mentioned substances having a highelectron-transport property. The layer for controlling transport ofelectrons controls transport of electrons, which enables adjustment ofcarrier balance. Such a structure is very effective in suppressing aproblem (such as shortening of element lifetime) caused by a phenomenonin which an electron passes through the light-emitting layer.

Further, an electron-injection layer may be provided so as to be incontact with the electrode functioning as a cathode. As theelectron-injection layer, an alkali metal, an alkaline earth metal, or acompound thereof, such as lithium fluoride (LiF), cesium fluoride (CsF),calcium fluoride (CaF₂), or the like can be employed. For example, alayer which contains both a substance having an electron-transportproperty and an alkali metal, an alkaline earth metal, or a compoundthereof, e.g., a layer of Alq which contains magnesium (Mg), can beused. Note that a layer including an electron-transport substance whichincludes an alkali metal or an alkaline earth metal is more preferablyused for the electron-injection layer, in which case electron injectionfrom the second electrode 120 proceeds efficiently.

When the second electrode 120 is used as a cathode, a metal, an alloy,an electrically conductive compound, a mixture thereof, or the likehaving a low work function (specifically, a work function of 3.8 eV orlower), can be used as a substance for the second electrode 120. As aspecific example of such a cathode material, an element belonging toGroup 1 or Group 2 of the periodic table, i.e., an alkali metal such aslithium (Li) or cesium (Cs), an alkaline earth metal such as magnesium(Mg), calcium (Ca), or strontium (Sr), an alloy containing any of thesemetals (such as MgAg or AlLi), a rare earth metal such as europium (Eu)or ytterbium (Yb), an alloy containing such a rare earth metal, or thelike can be used. However, when the electron-injection layer is providedbetween the cathode and the electron-transport layer, any of a varietyof conductive materials such as Al, Ag, ITO, indium oxide-tin oxidecontaining silicon or silicon oxide, and the like can be used regardlessof its work function as the cathode. Films of these conductive materialscan be formed by a sputtering method, an inkjet method, a spin coatingmethod, or the like.

It is preferable that, when the second electrode 120 is used as ananode, the second electrode 120 be formed using a metal, an alloy, aconductive compound, a mixture thereof, or the like having a high workfunction (specifically, a work function of 4.0 eV or higher).Specifically, indium oxide-tin oxide (ITO: indium tin oxide), indiumoxide-tin oxide containing silicon or silicon oxide, indium oxide-zincoxide (IZO: indium zinc oxide), indium oxide containing tungsten oxideand zinc oxide (IWZO), or the like can be used. These conductive metaloxide films are generally formed by a sputtering method; however, thefilms may be formed by applying a sol-gel method. For example, a film ofindium oxide-zinc oxide (IZO) can be formed by a sputtering method usingindium oxide, to which zinc oxide is added at 1 to 20 wt %, as a target.A film of indium oxide containing tungsten oxide and zinc oxide (IWZO)can be formed by a sputtering method using a target in which tungstenoxide and zinc oxide are mixed at 0.5 to 5 wt % and 0.1 to 1 wt %,respectively, with indium oxide. In addition, gold (Au), platinum (Pt),nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe),cobalt (Co), copper (Cu), palladium (Pd), a nitride of a metal (such astitanium nitride), and the like are given. By forming theabove-mentioned composite material so as to be in contact with theanode, a material for the electrode can be selected regardless of itswork function.

The element formation layer 116 can be formed through the above steps(see FIG. 2C).

Next, the element formation layer 116 is adhered to the upper support122 with the second adhesive layer 121, and then, at the separationlayer 201, separated from the formation substrate 200. Accordingly, theelement formation layer 116 is supported by the flexible upper support122, and the electrode 131 provided in the through-hole is exposed onthe surface of the element formation layer 116 which is opposite to theupper support 122 (see FIG. 2D).

As a material for the second adhesive layer 121, any of a variety ofcurable adhesives, such as a reactive curable adhesive, a thermalcurable adhesive, a photo curable adhesive such as an ultravioletcurable adhesive, or an anaerobic adhesive can be used.

As the upper support 122, a flexible film or substrate formed of any ofthe following materials can be used: an acrylic resin, a polyester resinsuch as polyethylene terephthalate (PET) or polyethylene naphthalate(PEN), a polyacrylonitrile resin, a polyimide resin, a polymethylmethacrylate resin, a polycarbonate (PC) resin, a polyethersulfone (PES)resin, a polyamide resin, a cycloolefin resin, a polystyrene resin, apolyamide imide resin, a polyvinylchloride resin, metal, and the like.

Over the upper support 122, a protective layer having low permeabilitymay be formed in advance, and examples thereof include a film containingnitrogen and silicon such as a film containing silicon nitride orsilicon oxynitride, a film containing nitrogen and aluminum such as afilm containing aluminum nitride, and the like.

Further, the step of FIG. 2D may be as follows: a separation support isused in place of the upper support 122 to perform separation, and theupper support is adhered with an adhesive agent; or alternatively, aseparation support is used to perform separation and then removed, andthe upper support is adhered with an adhesive agent.

Note that the following methods can be applied to the separation step,as appropriate: a method in which a separation layer is formed between aformation substrate and a layer that is to be separated, a metal oxidefilm is provided between the separation layer and the layer that is tobe separated, and the metal oxide film is weakened by crystallization tocarry out separation of the layer that is to be separated and providedover the metal oxide film; a method in which an amorphous silicon filmcontaining hydrogen is provided between a highly heat-resistantformation substrate and a layer that is to be separated, and theamorphous silicon film is removed by laser beam irradiation or etchingto carry out separation of the layer that is to be separated; a methodin which a separation layer is formed between a formation substrate anda layer that is to be separated, a metal oxide film is provided betweenthe separation layer and the layer that is to be separated, the metaloxide film is weakened by crystallization, and part of the separationlayer is etched away using a solution or a halogen fluoride gas such asNF₃, BrF₃, or ClF₃ to carry out separation at the weakened metal oxidefilm; a method in which a formation substrate provided with a layer thatis to be separated is mechanically removed or is etched away using asolution or a halogen fluoride gas such as NF₃, BrF₃, or ClF₃; or thelike. Alternatively, it is also possible to use a method in which a filmcontaining nitrogen, oxygen, hydrogen, or the like (e.g., an amorphoussilicon film containing hydrogen, a film of an alloy containinghydrogen, or a film of an alloy containing oxygen) is used as aseparation layer, which is irradiated with a laser beam so thatnitrogen, oxygen, or hydrogen contained in the separation layer isreleased as a gas to promote separation between a layer that is to beseparated and a substrate.

Further, the transfer step can be facilitated by using plural kinds ofseparation methods described above in combination. In other words,separation may be performed by physical force (by a machine or the like)after a separation layer is irradiated with a laser beam, etched using agas, a solution, or the like, or mechanically cut with a sharp knife sothat the separation layer and a layer that is to be separated are easilyseparated from each other.

Alternatively, a layer that is to be separated from a separation layermay be separated from a formation substrate, after liquid is made topenetrate an interface between the separation layer and the layer thatis to be separated, or while liquid such as water is poured into thisinterface.

Still alternatively, when the separation layer 201 is formed usingtungsten, it is preferable that the separation be performed whileetching the separation layer using a mixed solution of an ammoniumhydroxide and oxygenated water.

Next, the lower support 110 is adhered to the exposed surface of theelement formation layer 116 with the first adhesive layer 111. The lowersupport 110 is not adhered to the region where the external connectionterminal is to be provided; thus, the electrode 131 is exposed at thistime. After that, the external connection terminal 132 electricallyconnected to the electrode 131 is formed, and then the externalconnection portion 133 is connected to the external connection terminal132, whereby the light-emitting device of this embodiment which isillustrated in FIG. 1A can be fabricated (see FIG. 2E). Alternatively,without provision of the external connection terminal 132, an exposedportion of the electrode 131 may be used as an external connectionterminal.

As a material for the first adhesive layer 111, any of a variety ofcurable adhesives, such as a reactive curable adhesive, a thermalcurable adhesive, a photo curable adhesive such as an ultravioletcurable adhesive, or an anaerobic adhesive can be used.

As the lower support 110, a flexible film or substrate formed of any ofthe following materials can be used: an acrylic resin, a polyester resinsuch as polyethylene terephthalate (PET) or polyethylene naphthalate(PEN), a polyacrylonitrile resin, a polyimide resin, a polymethylmethacrylate resin, a polycarbonate (PC) resin, a polyethersulfone (PES)resin, a polyamide resin, a cycloolefin resin, a polystyrene resin, apolyamide imide resin, a polyvinylchloride resin, metal, and the like.

Over the lower support 110, a protective layer having low permeabilitymay be formed in advance, and examples thereof include a film containingnitrogen and silicon such as a film containing silicon nitride orsilicon oxynitride, a film containing nitrogen and aluminum such as afilm containing aluminum nitride, and the like.

Note that the upper support 122, the lower support 110, the firstadhesive layer 111, and the second adhesive layer 121 may include afibrous body therein. The fibrous body is a high-strength fiber of anorganic compound or an inorganic compound. A high-strength fiber isspecifically a fiber with a high tensile modulus of elasticity or afiber with a high Young's modulus. Typical examples of high-strengthfibers include a polyvinyl alcohol based fiber, a polyester based fiber,a polyamide based fiber, a polyethylene based fiber, an aramid basedfiber, a polyparaphenylene benzobisoxazole fiber, a glass fiber, and acarbon fiber. As the glass fiber, a glass fiber using E glass, S glass,D glass, Q glass, and the like are given. These fibers may be used in astate of a woven fabric or a nonwoven fabric, and impregnated with anorganic resin, and the organic resin is cured to obtain a structurebody. This structure body may be used as the upper support or lowersupport. When the structure body including the fibrous body and theorganic resin is used as the upper support or lower support, reliabilityof the element against bending or local pressure can be increased, whichis preferable.

In the case where the substrate or the adhesive layer in the directionwhere light emitted from the light-emitting element is extractedincludes the above-mentioned fibrous body, in order to reduce preventionof light emitted from the light-emitting element to the outside, thefibrous body is preferably a nanofiber with a diameter of less than orequal to 100 nm. Alternatively, refractive indexes of the fibrous bodyand the organic resin or the adhesive preferably match with each other.

In addition, the structure body obtained by the process in which thefibrous body is impregnated with the organic resin and the organic resinis cured can also be used to serve as both the first adhesive layer 111and the lower support 110 or both the second adhesive layer 121 and theupper support 122. At this time, as the organic resin for the structurebody, a reactive curable resin, a thermal curable resin, a UV curableresin, or the like which is better cured by additional treatment ispreferably used.

Next, another example of the method for manufacturing the light-emittingdevice in this embodiment is described with reference to FIGS. 3A to 3C.

The base insulating film 112 located over the formation substrate 200with the separation layer 201 interposed therebetween and thesemiconductor layer 250 and gate insulating film 251 located over thebase insulating film 112 are formed in a manner similar to that of theabove-described steps. After the gate insulating film 251 is formed, bypatterning and etching, a through-hole is formed in the gate insulatingfilm 251 and the base insulating film 112 (see FIG. 3A).

After that, the electrode 131 in the through-hole and the gate electrode252 are formed (see FIG. 3B). The electrode 131 and the gate electrode252 may be formed in the same step or using different materials indifferent steps, Note that the gate electrode 252 may be formed beforethe formation of the through-hole. In such a case, the protectiveinsulating film 253 may be formed over the gate electrode 252, and thenthe through-hole is formed in the protective insulating film 253, thegate insulating film 251, and the base insulating film 112.

Further, by forming the electrode 131 after oxidation treatment by O2ashing or the like on the exposed surface of the separation layer 201,adhesion between the electrode 131 and the separation layer 201 can bereduced to facilitate the separation in a later separation step.

After the electrode 131 and the gate electrode 252 are formed, theprotective insulating film 253 and the interlayer insulating film 254are formed as in the above-described step. Then, by patterning andetching, contact holes reaching the semiconductor layer 250 of the TFTare formed in the interlayer insulating film 254, the protectiveinsulating film 253, and the gate insulating film 251, and a contacthole 138 reaching the electrode 131 is formed in the interlayerinsulating film 254 and the protective insulating film 253. Then, theelectrode 137 connected to the electrode 131, the electrode 139 which isthe wiring electrode of the TFT, and the like are formed (see FIG. 3C).

The light-emitting device illustrated in FIG. 1B can be fabricated bythe above-described steps after the formation of the electrode 137 andthe electrode 139.

Note that in order to reinforce the external connection portion 133, aprotective member 450 is preferably provided to cover the lower support110 and the external connection portion 133, as illustrated in FIG. 4A.The protective member 450 can be formed using an epoxy resin, an acrylicresin, a silicone resin, or the like.

Alternatively, in the case where the external connection portion 133 isconnected to the light-emitting device before the lower support isadhered, the external connection portion can be protected in such amanner that the lower support 110 is adhered so as to cover a surface ofthe external connection portion 133, as in FIG. 4B. In this case, thelower support is provided to cover at least part of the externalconnection portion.

Then, FIGS. 5A to 5C are views each illustrating a module of thelight-emitting device (also referred to as an EL module) seen from thelower support side. In FIGS. 5A to 5C, a pixel portion 502, a sourceside driver circuit 504, and a gate side driver circuit 503 are formedover the first adhesive layer and the lower support 401. Further,reference numeral 402 indicates a region where the element formationlayer, the second adhesive layer, and the upper support are provided.The external connection terminal 132 and the external connection portion133 connected thereto are provided in a region that is on the lowersupport side of the element formation layer and not covered with thelower support. These pixel portion and driver circuits can be fabricatedaccording to the above manufacturing method.

Note that FIG. 5A illustrates an example in which the lower support hasa lateral length shorter than the upper support by the distance(indicated by reference numeral 520 in FIG. 5A) between the side of thelight-emitting device which is close to the external connection terminaland the side of the external connection terminal which is nearer to thecenter of the light-emitting device. FIG. 5B illustrates an example inwhich the lower support has a notch in the region where the externalconnection terminal is provided. FIG. 5C illustrates an example in whichthe lower support has an opening portion in the region where theexternal connection terminal is provided.

FIGS. 6A to 6C exemplify patterns of adhering the lower support forforming multiple light-emitting devices of the structure described inthis embodiment from a large-sized substrate. Each figure illustratesthe upper support 550 to which the element formation layer correspondingto the multiple light-emitting devices is transferred, portions 551 eachof which forms a light-emitting device after division, and the lowersupport 552. Note that FIGS. 6A, 6B, and 6C correspond to FIGS. 5A, 5B,and 5C, respectively. Patterning the lower support so as to be rolled upin advance, for example, facilitates automation of the step of adheringthe lower support. Further, the light-emitting device described in thisembodiment enables connecting the external connection portion to followadhering the lower support. Thus, after the lower support is adhered andthe multiple light-emitting devices are obtained by the division, theexternal connection portion can be connected. This is a process which isan important key to mass production of light-emitting devices.

The reason of the above importance is explained below. In themanufacture of medium- or small-sized light-emitting devices, formingmultiple devices from a large-sized substrate is necessary for costreduction. However, forming multiple light-emitting devices from alarge-sized substrate is extremely difficult if the light-emittingdevice has a structure in which the external connection terminal is notprovided on the lower support side of the element formation layer. Thisis because, for such a structure, the external connection portion needsto be connected before the upper support is adhered. In contrast, in thelight-emitting device described in this embodiment, the externalconnection terminal is provided on the lower support side of the elementformation layer. Accordingly, forming multiple light-emitting devicesfrom a large-sized substrate can be realized, which contributes to massproduction and cost reduction.

Further, the light-emitting devices illustrated in FIGS. 5A to 5C have astructure that enables the external connection portion to be connectedafter the lower support is adhered, in which the external connectionterminal is provided in the region that is on the lower support side ofthe element formation layer and not covered with the lower support. Inthe case where multiple light-emitting devices having such a structureare formed, the external connection portion can be connected afterdivision into individual light-emitting devices. Thus, the division inthis case is much easier than in the case where division into individuallight-emitting devices is performed after provision of the externalconnection portion. Therefore, such a structure is preferable because ofits suitability for mass production and automation.

FIGS. 7A and 7B are cross-sectional views of the example of thelight-emitting device illustrated in FIG. 5B taken along the line A-A′and the line B-B′, exemplifying the protective member protecting thelight-emitting device and the external connection portion.

The light-emitting device illustrated in FIG. 7A, where the steps up tothe connection of the external connection portion have been completed,is covered with an organic resin that has fluidity and transmits visiblelight. The organic resin is then dried, thereby forming a protectivemember 701. The protective member 701 can play a role in protecting notonly the external connection portion but also the upper support and thelower support from damage. As materials that can be used as theprotective member 701, there are an epoxy resin, an acrylic resin, asilicone resin, a variety of hard coating materials, and the like.

FIG. 7B illustrates an example of a method of adhering a lower support702 serving as a protective member. After the external connectionportion is formed, an adhesive agent is provided to cover a surface ofthe external connection portion, with which the lower support isadhered. The protection of the external connection portion can beenhanced by notching and rolling up the portion of the lower supportwhich sticks out of the external connection portion so as to cover aside of the light-emitting device and to reach the upper support, asillustrated in the cross section taken along the line B-B′. Note that aprotective member like the lower support 702 illustrated in FIG. 7B maybe provided, after the steps in which the external connection terminalis exposed to adhere the lower support and then the external connectionportion is connected.

The light-emitting device described above has a structure that canfacilitate provision of the external connection portion. This indicatesthat the light-emitting device is suitable for mass production.

(Embodiment 2)

In this embodiment, an electronic device including the light-emittingdevice described in Embodiment 1 as a part thereof will be described.

Examples of the electronic device including the light-emitting elementdescribed in Embodiment 1 include cameras such as video cameras ordigital cameras, goggle type displays, navigation systems, audioplayback devices (e.g., car audio systems and audio systems), computers,game machines, portable information terminals (e.g., mobile computers,mobile phones, portable game machines, and electronic book devices),image playback devices in which a recording medium is provided(specifically, devices that are capable of playing back recording mediasuch as digital versatile discs (DVDs) and equipped with a display unitthat can display images), and the like. Such electronic devices areillustrated in FIGS. 8A to 8E.

FIG. 8A illustrates a television receiver. The television receiverillustrated in FIG. 8A includes a housing 9101, a support 9102, adisplay portion 9103, speaker portions 9104, video input terminals 9105,and the like. In this television receiver, the display portion 9103 ismanufactured using the light-emitting device described in Embodiment 1.The television receiver is provided with the light-emitting devicedescribed in Embodiment 1 which has flexibility and long lifetime and iseasy to manufacture. This television receiver can be a relativelyinexpensive product while the display portion 9103 can be curved andlightweight.

FIG. 8B illustrates a computer. The computer illustrated in FIG. 8Bincludes a main body 9201, a housing 9202, a display portion 9203, akeyboard 9204, an external connection port 9205, a pointing device 9206,and the like. In this computer, the display portion 9203 is manufacturedusing the light-emitting device described in Embodiment 1. The computeris provided with the light-emitting device described in Embodiment 1which has flexibility and long lifetime and is easy to manufacture. Thiscomputer can be a relatively inexpensive product while the displayportion 9203 can be curved and lightweight.

FIG. 8C illustrates a mobile phone. The mobile phone illustrated in FIG.8C includes a main body 9401, a housing 9402, a display portion 9403, anaudio input portion 9404, an audio output portion 9405, operation keys9406, an external connection port 9407, and the like. In this mobilephone, the display portion 9403 is manufactured using the light-emittingdevice described in Embodiment 1. The mobile phone is provided with thelight-emitting device described in Embodiment 1 which has flexibilityand long lifetime and is easy to manufacture. This mobile phone can be arelatively inexpensive product while the display portion 9403 can becurved and lightweight. The lightweight mobile phone of this embodimentcan have a weight light enough to be carried even with additionalvalues, thereby being suitable as a multifunctional mobile phone.

FIG. 8D illustrates a camera. The camera illustrated in FIG. 8D includesa main body 9501, a display portion 9502, a housing 9503, an externalconnection port 9504, a remote control receiving portion 9505, an imagereceiving portion 9506, a battery 9507, an audio input portion 9508,operation keys 9509, an eyepiece portion 9510, and the like. In thiscamera, the display portion 9502 is manufactured using thelight-emitting device described in Embodiment 1. The camera is providedwith the light-emitting device described in Embodiment 1 which hasflexibility and long lifetime and is easy to manufacture. This cameracan be a relatively inexpensive product while the display portion 9502can be curved and lightweight.

FIG. 8E illustrates a display. The display illustrated in FIG. 8Eincludes a main body 9601, a display portion 9602, an external memoryinsertion portion 9603, a speaker portion 9604, operation keys 9605, andthe like. The main body 9601 may be provided with an antenna forreceiving a television broadcast, an external input terminal, anexternal output terminal, a battery, and the like. In this display, thedisplay portion 9602 is manufactured using the light-emitting devicedescribed in Embodiment 1. The flexible display portion 9602 can berolled up and stored in the main body 9601 and is suitable for beingcarried. The display is provided with the light-emitting devicedescribed in Embodiment 1 which has flexibility and long lifetime and iseasy to manufacture. The display portion 9602 can be suitable for beingcarried and is lightweight, and thus the display can be a relativelyinexpensive product.

As described above, the application range of the light-emitting devicedescribed in Embodiment 1 is so wide that the light-emitting device canbe applied to electronic devices of various fields.

This application is based on Japanese Patent Application serial no.2008-320939 filed with Japan Patent Office on Dec. 17, 2008, the entirecontents of which are hereby incorporated by reference.

Reference Numerals

110: lower support, 111: adhesive layer, 112: base insulating film, 114:pixel TFT, 115: TFT, 116: element formation layer, 117: electrode, 118:partition wall, 119: EL layer, 120: electrode, 121: adhesive layer, 122:upper support, 127: light-emitting element, 130: through-hole, 131:electrode, 132: external connection terminal, 133: external connectionportion, 134: interlayer insulating film, 135: wiring, 136: gateinsulating film, 137: electrode, 138: contact hole, 139: electrode, 200:formation substrate, 201: separation layer, 250: semiconductor layer,251: gate insulating film, 252: gate electrode, 253: protectiveinsulating film, 254: interlayer insulating film, 401: lower support,450: protective member, 502: pixel portion, 503: gate side drivercircuit, 504: source side driver circuit, 550: upper support, 552: lowersupport, 701: protective member, 702: lower support, 9101: housing,9102: supporting base, 9103: display portion, 9104: speaker portion,9105: video input terminal, 9201: main body, 9202: housing, 9203:display portion, 9204: keyboard, 9205: external connection port, 9206:pointing device, 9401: main body, 9402: housing, 9403: display portion,9404: audio input portion, 9405: audio output portion, 9406: operationkey, 9407: external connection port, 9501: main body, 9502: displayportion, 9503: housing, 9504: external connection port, 9505: remotecontrol receiving portion, 9506: image receiving portion, 9507: battery,9508: audio input portion, 9509: operation key, 9510: eye piece portion,9601: main body, 9602: display portion, 9603: external memory insertionportion, 9604: speaker portion, 9605: operation key.

1. A light-emitting device comprising: a first support; a firstinsulating film over the first support, wherein the first insulatingfilm has a through-hole; a thin film transistor over the firstinsulating film; a second insulating film over the thin film transistor;a second support over the second insulating film; an adhesive layerbetween the second insulating film and the second support; an electrodeover the second insulating film and in the through-hole; and an externalconnection portion below the first insulating film and electricallyconnected to the electrode, wherein the electrode is in contact with theadhesive layer.
 2. A light-emitting device comprising: a first support;an insulating film over the first support, wherein the insulating filmhas a through-hole; a thin film transistor over the insulating film,wherein the thin film transistor includes a semiconductor layer, a gateinsulating film and a gate electrode; a second support over the thinfilm transistor; an adhesive layer between the thin film transistor andthe second support; an electrode on the gate insulating film and in thethrough-hole; and an external connection portion below the insulatingfilm and electrically connected to the electrode, wherein the electrodeis in contact with the adhesive layer.
 3. A light-emitting devicecomprising: a first support; an insulating film over the first support,wherein the insulating film has a through-hole; a light-emitting elementover the insulating film; a second support over the light-emittingelement; an adhesive layer between the light-emitting element and thesecond support; an electrode in the through-hole; an external connectionterminal below the insulating film and electrically connected to theelectrode; and an external connection portion electrically connected tothe external connection terminal, wherein the electrode is in contactwith the adhesive layer.
 4. A light-emitting device comprising: a firstsupport; an insulating film over the first support, wherein theinsulating film has a through-hole; a light-emitting element over theinsulating film; a second support over the light-emitting element; anadhesive layer between the light-emitting element and the secondsupport; an electrode in the through-hole; and an external connectionportion below the insulating film and electrically connected to theelectrode, wherein the electrode is in contact with the adhesive layer.5. The light-emitting device according to any one of claims 1 to 4,wherein the first support and the second support are flexible.
 6. Thelight-emitting device according to any one of claims 1 to 4, wherein thefirst support is provided so as to expose the electrode in thethrough-hole.
 7. The light-emitting device according to any one ofclaims 1 to 4, further comprising a protective member below the firstsupport and the external connection portion.
 8. The light-emittingdevice according to any one of claims 1 to 4, wherein the first supporthas a notch portion so as to expose the electrode in the through-hole.9. The light-emitting device according to any one of claims 1 to 4,wherein the first support has an opening portion so as to expose theelectrode in the through-hole.
 10. The light-emitting device accordingto any one of claims 1 to 4, wherein a distance between a third side ofthe first support which is close to the external connection portion anda fourth side of the first support which is opposite to the third sideis shorter than a distance between a first side of the light-emittingdevice which is close to the external connection portion and a secondside of the light-emitting device which is opposite to the first side.11. The light-emitting device according to any one of claims 1 to 4,wherein the first support covers at least part of the externalconnection portion.
 12. An electronic device comprising thelight-emitting device according to any one of claims 1 to 4.